The present invention relates to devices for injecting, administering, delivering, dispensing or infusing a substance, and to methods for making and using such devices. More particularly, the present invention relates to a dose setting mechanism for an injection device, whereby a dose or quantity of a substance to be dispensed from or with the aid of the injection device can be set or selected.
Document DE 202 09 051 U1 discloses an injection device with a dose setting element which is locked in an end position. The injection device has a dose setting element able to effect a rotating movement relative to the housing of the device from a first direction of rotation as far as an end position and in an opposite direction of rotation to select a dose. The dose setting element is coupled with a conveying mechanism by which a selected dose can be dispensed from a reservoir of the injection device. An anti-rotation lock prevents the dose setting mechanism from effecting a rotating movement in the first direction of rotation beyond an end position.
Patent specification EP 0 828 527 B1 discloses an injection device with a forward feed sleeve which is able to slide forward longitudinally, wherein a printed dose indicator enables a reading to be taken of the dose to be injected. A mechanism is provided which prevents the injection device from being charged when a push rod is pulled out if the supply of an ampoule has been fully used.
German patent application No. 10 2005 001 159.4 discloses a dose setting mechanism for an injection device with a ratio transmitting system by which a dose quantity, a small quantity in particular, can be exactly set and dispensed.
Patent specification WO 2004/078239 A1 discloses a device for administering medicaments, comprising a housing with an internal thread, a dose selection sleeve with a thread which locates in the internal thread of the housing, a rotating sleeve which is releasably connected to the dose selection sleeve and a coupling disposed between the dose selection sleeve and the rotating sleeve. The two sleeves are able to rotate relative to the housing when the dose selection sleeve and the rotating sleeve are coupled. When the dose selection sleeve and the rotating sleeve are uncoupled, the dose selection sleeve is able to rotate relative to the housing whereas the rotating sleeve is locked to prevent it from rotating relative to the housing, thereby enabling an axial movement of the rotating sleeve so that a force is transmitted in the longitudinal direction toward the proximal end of the device to administer medicaments.